Stereospecific Synthesis of Fluorinated Pyrazolidinones and Isoxazolidines via a Catalyst‐Free 1,3‐Dipolar Cycloaddition of β‐Fluoroalkylated α,β‐Unsaturated 2‐Pyridylsulfones

Abstract

AbstractA highly atom‐economic, regio‐ and stereospecific synthesis of fluorinated pyrazolidinones and isoxazolidines is disclosed under catalyst‐ and additive‐free mild conditions. The diastereoselectivity with different type of 1,3‐dipoles is elucidated by using DFT calculations in CH3CN. Furthermore, a reaction using a chiral azomethine imine, a gram‐scale synthesis, and a reductive desulfonylation are also presented.